Unit Test #50

Select your answers to the following 10 questions from the pop-up menus in the right hand column. Clicking the "Begin Test Again" button will clear all the answers.

 

 

Q1:

 

What is the shape of the graph of a normal distribution?

A. rectangular
B. triangular
C. bell-shaped
D. bi-modal
Answer 1:

 

Q2:

 

Approximately what percentage of values lie within two standard deviations of the mean of a normal distribution? A. 34%
B. 68%
C. 95%
D. 99%
Answer 2:

 

Q3:

 

A normal distribution has a mean of 10 and a standard deviation of 2. What is the probability that a value chosen at random is more than 10? A. 0.34
B. 0.475 
C. 0.495
D. 0.5
Answer 3:

 

Q4:

 

For the distribution in question 3, what is the probability that a value chosen at random is less than 12? A. 0.34 
B. 0.5
C. 0.84
D. 0.95
Answer 4:

 

Q5:

 

For the distribution in question 3, what is the probability that a value chosen at random is between 10 and 13?

A. 0.5
B. 0.4332
C. 0.4987
D. 0.9332

Answer 5:

 

Q6:

 

A distribution with the same mean, median and mode is always called a normaldistribution. A. True
B. False
Answer 6:

 

Q7:

 

What is the mean of the standard normal distribution? A. 0
B. 0.5
C. 1
D. 50
Answer 7:

 

Q8:

 

Peoples' weights are normally distributed with a mean of 70 kg and a standard deviation of 10 kg.

What percentage of people would have a weight between 60 kg and 80 kg?

A. 34%
B. 68%
C. 95%
D. 99%
Answer 8:

 

Q9:

 

For the people in question 8, what percentage of people would have a weight greater than 45 kg

A. 49.38
B. 99.38 
C. 49.50
D. 99.50

Answer 9:

 

Q10:

 

What is the standard deviation of the standard normal distribution? A. 0
B. 0.5
C. 1
D. 50
Answer 10: